On Wed, Sep 09, 2020 at 04:29:50PM -0400, Joe Lawrence wrote: > On 9/9/20 3:49 PM, Kees Cook wrote: > > > > On Fri, Jun 26, 2020 at 01:59:43PM -0700, Kees Cook wrote: > > > Instead of full GNU diff (which smaller boot environments may not have), > > > use "comm" which is more available. > > > > > > Reported-by: Naresh Kamboju <naresh.kamboju@xxxxxxxxxx> > > > Link: https://lore.kernel.org/lkml/CA+G9fYtHP+Gg+BrR_GkBMxu2oOi-_e9pATtpb6TVRswv1G1r1Q@xxxxxxxxxxxxxx > > > Fixes: f131d9edc29d ("selftests/lkdtm: Don't clear dmesg when running tests") > > > Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> > > > > Shuah, this really needs to land to fix lkdtm tests on busybox. Can > > you add this to -next? (Or is it better to direct this to Greg for the > > lkdtm tree?) > > > > Thanks! > > > > -Kees > > > > > --- > > > tools/testing/selftests/lkdtm/run.sh | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > diff --git a/tools/testing/selftests/lkdtm/run.sh b/tools/testing/selftests/lkdtm/run.sh > > > index 8383eb89d88a..5fe23009ae13 100755 > > > --- a/tools/testing/selftests/lkdtm/run.sh > > > +++ b/tools/testing/selftests/lkdtm/run.sh > > > @@ -82,7 +82,7 @@ dmesg > "$DMESG" > > > ($SHELL -c 'cat <(echo '"$test"') >'"$TRIGGER" 2>/dev/null) || true > > > # Record and dump the results > > > -dmesg | diff --changed-group-format='%>' --unchanged-group-format='' "$DMESG" - > "$LOG" || true > > > +dmesg | comm -13 "$DMESG" - > "$LOG" || true > > > cat "$LOG" > > > # Check for expected output > > > -- > > > 2.25.1 > > > > > > > > > -- > > > Kees Cook > > > > Hi Kees, > > You may want to consider a similar follow up to the one Miroslav made to the > livepatching equivalent: > > https://lore.kernel.org/live-patching/nycvar.YFH.7.76.2008271528000.27422@xxxxxxxxxxxxx/T/#m1c17812d2c005dd57e9a299a4a492026a156619e > > basically 'comm' will complain if two lines from dmesg have the same > timestamp prefix and their text portions are not sorted. Ah-ha! Thank you. I will send a v2. :) -- Kees Cook
